The Tomarctus is the species that most canids (bears , dogs, wolves ) evolve from. It is also the starting place of the Vulpes genus. There are two species of Tomarctus and they are T. Bevirostris and T. Hippophaga. The Tomarctus lived in the late Early Minocene to the Early Barstovian age of the Middle Minocene which is around 23 - 16 million years ago. The Tomarctus is estimated to have existed for nearly 7 million years before going extinct.
Scientific
Classification
Kingdom
Animalia
Phylum
Chordata
Class
Mammalia
Order
Carnivora
Family
Canidae
Subfamily
Borophaginae
Genus
Tomarctus
Habitat
The only evidence of the Tomarctus is found in North America, mainly within the USA. The Tomarctus Bevirostris is found within a range of as west as California, east as Maryland, as north as Montana and as far south as Panama. The Tomarctus Hippophaga had a smaller range than the T. Bevirostris. it was first discovered in Nebraska and later found in California and as north as the Canadian border.
The period of that the Tomarctus lived in was the Miocene Epoch of the Neogene period. This was a period where the climate of the earth was slightly cooler and drier then before. This meant the grasslands that existed all over the world were expanding as forests receded, The area that the tomarctus lived in were mostly grassland with mountains forming in some parts of western North America.
Adaptations
Structural 1
One of the structural adaptations known about the tomarctus is common in most canids. These are pads on the bottom of their feet to protect them from sharp objects that they might step on. These include sharp rocks, oyster shells and sharp animal bones.
This is useful when the tomarctus is being pursued and does not look on what it is stepping on.
The evolutionary pressure for this adaptation could perhaps have been the death of some tomarctus from infected cuts on the bottom of their feet. This caused the bottom of the tomarctus's feet to develop calluses which eventually turned into pads over the 7 million years of its existence.
Structural 2
Another structural adaption of the tomarctus is its four-toed foot. This effectively narrowed the foot which meant the tomarctus could exert more force on the ground on a smaller surface. This would mean that the tomarctus would run faster. This is useful in catching smaller prey that are fast and more agile than the tomarctus.
This adaptation was probably the result of the need to catch prey. As the tomarctus preyed on small rodents, it needed to run faster in order to catch up to it. This meant that the five toes in its foot were making its foot heavier and by losing this toe, the tomarctus could catch up to its prey.
Behavioral 1
One of the behavioral adaptations that is found in the tomarctus is that unlike other canids, the tomarctus is a solitary hunter which means it only comes into contact with others of its kind only in the breeding season. This means that it can spend time fending for itself and does not have to waste time and energy defending its pack.
This adaptation could have arisen due to the need for more energy. The diet of the tomarctus was small rodents which would meant that sharing food would have been difficult of everyone was to be satisfied. Being a solitary hunter meant that the tomarctus does not need to hunt for more than one animal and thus able to consume more energy,
Behavioral 2
Another noticeable behavior of the tomarctus is that it is a carnivore.This is seen from the large canines and incisors in the tomarctus's mouth. This was a very good adaptation during this time as prey was abundant because of development grasslands across the Great Plains of North America.
A possible pressure that caused this adaptation could have been the need for a better growth. As meat contains proteins needed to build strong muscles, the tomarctus needed to eat large amounts of it to be able to grow to its optimal size.
Physiological 1
One of the ways the tomarctus adapted physiologically is in its size. It was found to be massive in size, around the size of a bear. Thus earning its name, Tomarctus, which means "almost a bear". The size of the tomarctus served it in many ways. Having such a big body would mean that it was stronger than smaller animals, thus making it able to hunt for larger prey which means more it can hunt less.
The environmental pressure that could've given rise to the size of the tomarctus could have been the need to survive in a time when everything when size dictated if you survived or not. The bigger the tomarctus the more chances it will have at surviving because of its greater strength and stamina.
Extinction Pressure
The tomarctus probably became extinct because it evolved into better versions of itself, each being able to survive better in its given environment. The tomarctus is the ancestor of all canids ranging from the fruit eating hyena-like animals to the bone crushing canids much like the bear and the wolf. As the tomarctus radiated into different branches, the original species had to compete with the more suited species. This meant there would be an insufficient amount of food to support both species and the tomarctus eventually died out. Another reason could have been the size of the tomarctus. The size of thse tomarctus did not allow for speed so as slow moving animals started to become extinct, the food chain was disrupted and the tomarctus became extinct.
TomarctusRed Fox (Modern Animal) >>
The Tomarctus is the species that most canids (bears , dogs, wolves ) evolve from. It is also the starting place of the Vulpes genus. There are two species of Tomarctus and they are T. Bevirostris and T. Hippophaga. The Tomarctus lived in the late Early Minocene to the Early Barstovian age of the Middle Minocene which is around 23 - 16 million years ago. The Tomarctus is estimated to have existed for nearly 7 million years before going extinct.
Scientific
Classification
Kingdom
Animalia
Phylum
Chordata
Class
Mammalia
Order
Carnivora
Family
Canidae
Subfamily
Borophaginae
Genus
Tomarctus
Habitat
The only evidence of the Tomarctus is found in North America, mainly within the USA. The Tomarctus Bevirostris is found within a range of as west as California, east as Maryland, as north as Montana and as far south as Panama. The Tomarctus Hippophaga had a smaller range than the T. Bevirostris. it was first discovered in Nebraska and later found in California and as north as the Canadian border.The period of that the Tomarctus lived in was the Miocene Epoch of the Neogene period. This was a period where the climate of the earth was slightly cooler and drier then before. This meant the grasslands that existed all over the world were expanding as forests receded, The area that the tomarctus lived in were mostly grassland with mountains forming in some parts of western North America.
Adaptations
Structural 1
One of the structural adaptations known about the tomarctus is common in most canids. These are pads on the bottom of their feet to protect them from sharp objects that they might step on. These include sharp rocks, oyster shells and sharp animal bones.This is useful when the tomarctus is being pursued and does not look on what it is stepping on.
The evolutionary pressure for this adaptation could perhaps have been the death of some tomarctus from infected cuts on the bottom of their feet. This caused the bottom of the tomarctus's feet to develop calluses which eventually turned into pads over the 7 million years of its existence.
Structural 2
Another structural adaption of the tomarctus is its four-toed foot. This effectively narrowed the foot which meant the tomarctus could exert more force on the ground on a smaller surface. This would mean that the tomarctus would run faster. This is useful in catching smaller prey that are fast and more agile than the tomarctus.This adaptation was probably the result of the need to catch prey. As the tomarctus preyed on small rodents, it needed to run faster in order to catch up to it. This meant that the five toes in its foot were making its foot heavier and by losing this toe, the tomarctus could catch up to its prey.
Behavioral 1
One of the behavioral adaptations that is found in the tomarctus is that unlike other canids, the tomarctus is a solitary hunter which means it only comes into contact with others of its kind only in the breeding season. This means that it can spend time fending for itself and does not have to waste time and energy defending its pack.This adaptation could have arisen due to the need for more energy. The diet of the tomarctus was small rodents which would meant that sharing food would have been difficult of everyone was to be satisfied. Being a solitary hunter meant that the tomarctus does not need to hunt for more than one animal and thus able to consume more energy,
Behavioral 2
Another noticeable behavior of the tomarctus is that it is a carnivore.This is seen from the large canines and incisors in the tomarctus's mouth. This was a very good adaptation during this time as prey was abundant because of development grasslands across the Great Plains of North America.A possible pressure that caused this adaptation could have been the need for a better growth. As meat contains proteins needed to build strong muscles, the tomarctus needed to eat large amounts of it to be able to grow to its optimal size.
Physiological 1
One of the ways the tomarctus adapted physiologically is in its size. It was found to be massive in size, around the size of a bear. Thus earning its name, Tomarctus, which means "almost a bear". The size of the tomarctus served it in many ways. Having such a big body would mean that it was stronger than smaller animals, thus making it able to hunt for larger prey which means more it can hunt less.The environmental pressure that could've given rise to the size of the tomarctus could have been the need to survive in a time when everything when size dictated if you survived or not. The bigger the tomarctus the more chances it will have at surviving because of its greater strength and stamina.
Extinction Pressure
The tomarctus probably became extinct because it evolved into better versions of itself, each being able to survive better in its given environment. The tomarctus is the ancestor of all canids ranging from the fruit eating hyena-like animals to the bone crushing canids much like the bear and the wolf. As the tomarctus radiated into different branches, the original species had to compete with the more suited species. This meant there would be an insufficient amount of food to support both species and the tomarctus eventually died out. Another reason could have been the size of the tomarctus. The size of thse tomarctus did not allow for speed so as slow moving animals started to become extinct, the food chain was disrupted and the tomarctus became extinct.Bibliography
Kathleen Munthe (1989). The Skeleton of the Borophaginae. Retrieved 20th July 2010 from: http://books.google.com/books?id=V6zJEV2MEDEC&pg=PR11&lpg=PR11&dq=tomarctus+solitary&source=bl&ots=wPUrrxtSe8&sig=TFCd5QzDnNW53p1emEEYKvB1Emc&hl=en&ei=DQNATOaNGYO0cJSqkdIP&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBIQ6AEwAA#v=onepage&q=tomarctus%20solitary&f=falseInfoHub (2005) Tomarctus - Ancestor of Dogs and Wolves Retrieved 20th July 2010 from:http://www.infohub.com/forums/archive/index.php?t-2544.html
Wikipedia (2010) Tomarctus Retrieved 19th July 2010 from: http://en.wikipedia.org/wiki/Tomarctus
The Searching Wolf (n.d.) Chronology of Wolf Evolution Retrieved 18th July 2010 from: http://www.searchingwolf.com/wevolve.htm